Hydraulic valve.



E. W. MARSHALL. HYDRAULIC VALVE.

APPLICATION FILED JUNE 23, 1906'.

Patented Jan. 19, 1909.

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UNITED STATES PATENT OFETCE.

ERNEST W. MARSHALL, OF YONKERS, NEW YORK, ASSIGNOR TO OTIS ELEVATOR COM- IANY, OF JERSEY CITY, NEW JERSEY, A CORPORATION OF NEW JERSEY.

HYDRAULIC VALVE To all whom 'it may concern Be it known that I, ERNEST IV. MARSHALL, a citizen of the United States, and a resident of Yonkers, in the county of IVestchest'er and State of New York, United States of America, have invented cert-ain new and useful Improvements in Hydraulic Valves, of which the following is a specification.

My invention relates to a hydraulic valve of that type which is operated by means of a pilot valve, and its object is to improve upon structures of this kind.

I will describe my invention in the following specication and point out the novel features thereof in claims.

Referring to the drawings, Figure 1 is an elevation, partly in section, of a hydraulic elevator with my improved valve connected thereto. Fig. 2 is an enlarged sectional elevation of my improved valve and its connected parts. Fig. 3 is a section of a portion of the valve shown in Fig. 2, the section being taken through the line A B of F ig. 2

and the view taken in the direction of the arrows. Fig. 4 is a sectional view of a modiiication of my invention. Fig. 5 is a sectional view of some of the parts shown in Fig. t but somewhat differently arranged.

Like characters of reference designate corresponding parts in all of the figures.

10 designates a portion of an elevator-car which is attached to the top of a plunger 11. This plunger 11 passes through a stufiingbox 12 and into a cylinder 13.

20 designates a main valve and 30 designates a pilot valve.

The main valve 20 comprises an inlet port 21 which is connected to a suitable source of hydraulic supply under pressure. 22 designates an outlet port and 23 designates a port which may be connected to the cylinder 13 as shown in Fig. 1. The valve 2O also comprises a main valve cylinder 24C and a motor cylinder 25 of larger diameter. A valverod or stem 26 extends through these two cylinders 24 and 25 and has attached to it pistons 27 and 2S which are arranged to be moved in the main valve cylinder 24:, and a piston 29 which is arranged to be moved in the motor cylinder 25. 21A designates a port which may be connected to the inlet port 21 and serves the function of maintaining the constant pressure supply in the space between the pistons 28 and 29.

The pilot valve 30 comprises a cylinder 34C and a piston 37. An inlet port 31 and an Specification of Letters Patent.

Application filed June 23, 1906.

Patented Jan. 19, 1909.

Serial No. 322,996.

outlet port 32 are arranged, as shown, above and below the piston 37, and a third port 33 is arranged intermediate these two ports, which port 33 is connected by a pipe 35 to the motor cylinder 25. The valvestem 37A of the pilot valve is connected to the piston 37 and extends up through a stufling-box to a floating-lever 51 to which it is pivoted at 52. This floating-lever 51 is also connected to the stem 2G of the main valve which extends up through a stuiingbox at the top of the valve by a link 511 which is pivoted at 53 to the floating-lever, and at 55 to the valve-stem 26. The floating-lever 51 is connected by some suitable mechanism to be operated from the elevator car 10; for example, a hand-rope 50 may be connected to one end of the iioating-lever and extended up through the elevator-car within reach of an operator in the car.

The parts above described are well-known in the art, and before proceeding with the description of my invention I will point out their operation.

If an operator in the car desires the car to move upward he will raise the right hand end of the loatingelever 51 by means of the hand-rope and will thereby open a hydraulic connection between the port 33 and the exhaust port 32. The exhaust port 32, as has been pointed out, is connected to the motor cylinder 25. Any water which is in the motor cylinder 25 may therefore flow out through the pipe 35 and the exhaust port 32. As the piston 29 in the motor cylinder is larger than the piston 28 in the main cylinder, the hydraulic pressure which enters through port 21 and the port 21A will cause the valve-stein 26 and its connected parts to move downward. hydraulic supply through port 21, valve cylinder 24E and port 23 to the cylinder 13. The hydraulic pressure, then, in cylinder 13, will cause the plunger 11 and the car to move upward, and this upward movement will continue as long as the pressure supply remains connected to the elevator cylinder. The mechanical connections between the main valve and the pilot valve will cause the pilot-valve piston 37 to be moved down again to its central position when the valvestem 2G has been moved an amount proportional to the movement which the operator has given to the lever 51, so that the pilot valve will become automatically closed after it has performed its function of causing the This will connect the pistons of the main valve to be moved. I/VhenV the operator desires to stop the upward movement of the elevator he will move the Heating-lever 51 by the hand-rope in the opposite direction until the inlet port 3l is opened to port 33, and through pipe 35 to the motor cylinder 25. The hydraulic pressure under the piston 29 will then cause the valve-stem 26 and its connected parts to be raised up again until the pilot-valve piston 37 again closes the `port 33. A further downward movementr of the pilot-valve piston 37 will cause the hydraulic pressure to continue the upward movement of the valve-stem 26 and its connected parts until the port 23 is connected to the exhaust port 22. This will allow the water in cylinder 13 to ow out through the exhaust port 22, and the elevatQr will then move downward. The operator may again bring the elevator-car to rest by a .suitable operation of the floating-lever 5l. As the parts above described and their operation are well-known in the art a more extended description of them is not thought necessary.

' In many cases it is desirable to have a valve open quickly and close slowly, and it is one of the objects of this invention to supply an efficient and simple arrangement of parts to accomplish this result. For this purpose, then, I divide the connection between the pipe 35 and the motor cylinder 25 into two paths and interpose a check-valve in each or' these paths, which check-valves operate in opposite directions.

In the arrangement shown in Figs. 2 and 3 the hydraulic supply, entering into motor cylinder 25 from the pipe 35, is taken through a port 39 in the motor cylinder after passing through a check-valve 37. The hydraulic supply passing out of motor cylinder 25 into pipe 35 is taken through a port 38 and passes through a check-valve 36. A throttling-blade 4() is attached to the valve-stem 26 and held rigidly in place on the rod by means of a set-screw 4l. rlhis throttling-blade 40 is arranged to pass over and to partially close either one of the ports 38 or 39 when the main valve 2O has been opened in one direction or the other. Thus the blade 40 in conjunction with the port 38 constitutes a throttling valve for the passage into vpipe 35 through check-valve 36, and in conjunction with the port 39 this blade constitutes a throttling valve for the passage from the pipe 35 through the check-valve 37 into the cylinder 25. If the main valve stem and its connected pistons have been raised by a supply of water passing through pipe 35, check-valve 37 and port 39 into motor cylinder 25, the throttling-blade 40 will have been moved thereby over port 38. This upwardzmovement of the valve-stem and its pistons may be as rapid as desired by having the pilot'va-lve and its connected parts'of desired size. Now, when it is desired to bring the valve-stem 26 and its connected piston baci; again to their central position, the pilot valve may be so manipulated as to allow the water to flow out of the motor cylinder25. It may be seen that this water can not pass out through the port 39 because the check-valve 37 is arranged to prevent any outward flow of water. lhatever water, then, passes out of the motor cylinder must pass through port 38 which is now partially closed by the throttling-blade 40. The proportional part of the area of this port 38, which is closed by the throttlingblade 40, may be as large oras small as desired, but it may be seen that as the passage for the water through this port is now restricted, the movement of the valve-stem 26 and its connected parts must be comparatively slow. At'ter the valve-stem 26 and its connected parts have reached their central position the throttling-blade 40 will yhave been moved ott from the port 38 so that the latter is again free to move the valve quickly in case it is desired to move it down away from its central position. Similarly, when the operator has moved the valve-stem 26 and its connected parts downward by allowing the water to liow out of the motor cylinder 25 through the port 3S and checkvalve 36, the throttling-blade 40 will be moved down over the port 39 so that when it is desired to have the main valve brought back to its central position by allowing the water to flow into motor cylinder 25 it can only do so through the resL 1icted opening which is formed by port 39 which is now partially closed by the throttling-blade 40.

In F ig. 4 I have shown a modification of my invention in which case an ordinary standard elevator-valve may be used with but slight change of construction. In this case the valve-stem 26 is carried down through a stuffing-box 26A at the bottom of `the valve, and a cam member 42 is rigidly attached to it. The two ports 38A and 39A may be placed in the bottom of the valve and the check-valves 36A and 37B vinterposed in the pipes leading from these ports in the manner already described. In this case, however, a rotary throttling-valve 43 is interposed in the pipe leading from t-he port 39A and this valve is provided with an operating arm 44 which extends into ther path of travel of the cam member 42. A similar rotary throttling-valve 45 is interposed in the pipe leading from the port 38A and is provided with an operating arm 46 which extends into the pathy of travel of the cani member 42. vIn this case, if the valve-stem 26 and its connected parts are moved upward by water passing through port39A the cam member 42, acting upon operating arm 46, will rotate the valve 45 and cause it to partially close the passage in the pipe leading from port 38A. Consequently, when it is desired to allow the water to run out of the motor cylinder 25 through port 38A and its connected pipes the water can escape but slowly, because the passage is restricted by the throttling-valve 45. The upward movement of the valve-stem 26 and its connected parts may then be a rapid one and its downward movement considerably slower. This holds good only until the valve-stem 26 has reached its central position and its connected pistons have closed the main valve. When the valve-stem 26 is in its central position both of the throttling-valves 43 and 45 are open so that the valve may be moved quickly in either direction. After it has been moved in either direction, however, its return to the central position will be comparatively slow. I have shown this valve connected to a hydraulic elevator of the plunger type as its use in this connection is decidedly advantageous. Inv such elevators it is desirable to open the valve quickly either for t-he upward or downward movement of the elevator-ear because there is a large amount of weight, the inertia of which must be overcome quickly in order to get the car into motion quickly. It is also desirable to make it impossible for an operator to close such a valve too quickly because the momentum of the moving parts is so great that a sudden stop of the flow of water in either direction causes the car to come to rest with a dis agreeable vibrating movement. It is clear that this invention is not limited to use in conjunction with hydraulic elevators, but that it may be used in connection with any other arrangement where it is desired to have the valve move at a diierent rate of speed from its central position than it does back to its central position.

The valve may be arranged to move away from its central position slowly and to move back to its central position quickly by a very simple change in the arrangement of parts. Such an arrangement is shown in Fig. 5 in which the cam member 42A is arranged to hold the two throttling-valves 43 and 45 in their partially closed position when the valve-stem 26 is in its central position. IVhenever water is allowed to pass through throttling-valve 43 and check-valve 37B into the motor cylinder 25 it is clear that the passage is restricted by the position of the throttling-valve 48, and it will remain in this restricted position during the upward movement of the valve-stem 26 and its connected parts; but in this case, when the valve-stem 26 is raised above its central position it allows the throttling-valve 45 to be opened so that when the water is discharged from the motor cylinder 25 it will flow out rapidly and allow the main valve to return to its central position quickly. In a similar manner the valve-stem 26 may be moved downward from its central position slowly and returned to its central position quickly. I have illustrated two modiiieations of my invention to show that it is not confined to any particular construction, but that it may be made in various forms.

What I claim is l. A motor comprising a cylinder and a piston, two ports in said cylinder, and means for partially closing one of said ports directly by a movement of the motor piston in one direction and for closing the other oi said ports directly by a movement of the motor piston in the opposite direction.

2. A motor comprising a cylinder and a piston, a port leading to the cylinder, a check-valve associated with said port and arranged to prevent the flow ot' fluid through said port :trom the cylinder, a second port leading from the cylinder, a check-valve associated with said second port and arranged to prevent the flow of fluid through said port to the cylinder, said motor piston beino actuated by a flow of fluid through sait ports; and means for partially closing one of said ports when the motor piston is actuated by the flow of fluid through the other of said ports.

3. A motor comprising a cylinder, a movable piston therein, a port leading to the cylinder, a cheek-valve associated with said port and arranged to prevent the liow of fluid through said port from the cylinder, a second port leadine' from the cylinder, a check-valve associated. with said second port and arranged to prevent the flow of fluid through said port to the cylinder, said motor piston being actuated by the flow of fluid through said ports, and a throttling-blade connected to the movable piston and ar- 105 ranged to partially close either of said ports when said piston is actuated by the flow of fluid through the other of said ports.

4. A main valve, a motor comprising a cylinder and a piston associated therewith, 110 two ports in the motor cylinder, and means for partially closing one of said ports direetly by a movement of the piston from its central position in one direction, and for partially closing the other of said ports di- 115 reetly by a movement of the piston in the other direction.

5. A main valve, a motor comprising a cylinder associated therewith, a piston-rod,

a piston on said rod within said cylinder, 120 two ports in the motor cylinder, and a throti tling-blade attached to the piston-rod, said blade being arranged to partially close one of said ports by a movement of the pistonrod in one direction and to partially close 125 the other oi the ports by a movement of the piston-rod in the other direction.

6. A main valve, a motor comprisino' a cylinder and a piston associated therewith,

a pilot valve, two ports in the motor cylin- 130I der, said ports being connected with the pilot -valve, and means in the motor for partially closing one of said ports directly by a movement of the motor piston from its central position in one direction, and for partially closing the other of said ports directly by a movement of the motor piston in the opposite direction.

7. A main valve, a motor comprising a cylinder and adapted to move the main valve, a movable piston in said motor, pilot valve for controlling the movement of the main valve and the motor, two ports 'in the motor cylinder through which the motor is connected with the pilot valve, and a throttling-blade connected with said mov able piston, said blade being arranged to partiallyclose one of the ports in the motor cylinder when the movable piston is moved from its central position in one direction and to partially close the other of said ports when the movable piston is moved from its central position in the opposite direction.

S. A main valve cylinder, a motor cylinder in alinement therewith, a piston-rod, pistons in said cylinders, said pistons being attached to the piston-rod, a pilot valve for controlling the movement of the pistons of the main valve and the motor, mechanical connections between the piston-rod and the pilot valve; two ports in the motor cylinder, a hydraulic connection between said ports and the-pilot valve, and a throttling-blade attached to the piston-rod, said blade being arranged to partially close one of said ports by a movement of the piston-rod from its central position in one direction, and to partially close the other of the portsby a movei ment of the piston-rod from its central po-` sition in the other direction.

9. A valve, a motor therefor, two passages to said motor, and means directly attached to the valve and actuated by the movement of the same for changing but not closing the size of the passages. Y

l0. A valve comprising a piston, a motor therefor, two passages to said motor and means directly attached to the piston and actuated by a movement of the same for changing but not closing the size of one of the passages by a movement of the piston from its cent-ral position in one direction, and for changing but not closing the size of the other of the passages by a movement of the piston from its central position in the opposite direction.

ll. A main valve, a motor comprising a cylinder and a piston associated therewith, a pilotwalve, two ports in the motor cylinder, hydraulic connections between the pilotvalve and said. ports, said motor piston being actuated by a flow of iiuid through said ports, a -tlirottling-blade operated by the m0- tor piston and arranged to partially close that port through which fluid must flow to cause the motor pist-on to close the main valve whenever the main valve has been moved away from its central position.

In testimony whereof I have signed my name to this specification in the presence of two subscribing witnesses.

ERNEST lV. MARSHALL.

Vitnesses z FRANCIS B. lVooD, ELLA TUGH. 

